b'Figure 4. Post-transient neutron radiography of SETH-C, -D, and -E capsules using TREATs neutron radiography capability.way for greater instrument density cause cladding melt. The SETH-D in more complex geometries in transient was designed to achieve future designs. partial cladding melt by using ECFs The ECFs measured by calorimetrymeasured in previous tests to predict and gamma spectroscopy in theperformance using the BISON code. SETH-A through -C irradiations wereThis target condition was achieved, found to be in good agreement withgiving observational confirmation each other ranging from 2.0 to 2.2. J/ of the previously measured ECFs, as gUO 2 MJ. The SETH -C rodlet, whichindicated by post-transient neutron achieved a peak cladding temperatureradiography where only the top of 1378 C, according to pyrometerpellet was held by surviving cladding. measurements, was characterized inSETH-E caused gross cladding melting TREATs neutron radiography standand the transient was shaped to and later extracted from its capsule infavor observation of fuel downward an unshielded glovebox (confirmingmotion by the FMMS. Both SETH-D the viability of the MARCH lowand -E far exceeded the survival activation approach to postirradiationand calibration range for cladding exam for fresh specimens) where boththermocouples while the pyrometer activities confirmed that the rodletmeasurements successfully measured was intact and undisturbed. temperatures beyond the melting point of the zirconium alloy cladding, The final irradiations in the SETHdemonstrating the value of this series (SETH-D and -E) wereadvanced measurement method in performed at even higher energy totransient testing.2019|AFC ACCOMPLISHMENTS 117'